package com.lovcreate.Controller;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Iterator;
import java.util.List;

/**
 * Created by Administrator on 2016/7/27.
 */
@WebServlet(name = "UploadServlet",urlPatterns = {"/UploadServlet"})
public class UploadServlet extends HttpServlet {

    private boolean isMultipart;
    private String filePath;
    private int maxFileSize = 50 * 1024;
    private int maxMemSize = 4 * 1024;
    private File file;

    public void init() {
        // 获取文件将被存储的位置
        filePath = getServletContext().getInitParameter("file-upload");
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // 检查我们有一个文件上传请求
        isMultipart = ServletFileUpload.isMultipartContent(request);
        response.setContentType("text/html; charset=utf-8");
        PrintWriter out = response.getWriter();
        if( !isMultipart ){
            out.println("<html>");
            out.println("<head>");
            out.println("<title>Servlet upload</title>");
            out.println("</head>");
            out.println("<body>");
            out.println("<p>No file uploaded</p>");
            out.println("</body>");
            out.println("</html>");
            return;
        }
        DiskFileItemFactory factory = new DiskFileItemFactory();
        // 文件大小的最大值将被存储在内存中
        factory.setSizeThreshold(maxMemSize);
        // Location to save data that is larger than maxMemSize.
        factory.setRepository(new File("F:\\temp"));

        // 创建一个新的文件上传处理程序
        ServletFileUpload upload = new ServletFileUpload(factory);
        // 允许上传的文件大小的最大值
        upload.setSizeMax(maxFileSize);

        try {
            // 解析请求，获取文件项
            List fileItems = upload.parseRequest(request);
            // 处理上传的文件项
            Iterator i = fileItems.iterator();

            out.println("<html>");
            out.println("<head>");
            out.println("<title>Servlet upload</title>");
            out.println("</head>");
            out.println("<body>");
            while ( i.hasNext () )
            {
                FileItem fi = (FileItem)i.next();
                if ( !fi.isFormField () )
                {
                    // 获取上传文件的参数
                    String fieldName = fi.getFieldName();
                    String fileName = fi.getName();
                    String contentType = fi.getContentType();
                    boolean isInMemory = fi.isInMemory();
                    long sizeInBytes = fi.getSize();
                    // 写入文件
                    if( fileName.lastIndexOf("\\") >= 0 ){
                        file = new File( filePath +
                                fileName.substring( fileName.lastIndexOf("\\"))) ;
                    }else{
                        file = new File( filePath +
                                fileName.substring(fileName.lastIndexOf("\\")+1)) ;
                    }
                    fi.write( file ) ;
                    out.println("Uploaded Filename: " + fileName + "<br>");
                }
            }
            out.println("</body>");
            out.println("</html>");

        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }
}
